This disclosure relates to an improved magnetic microplate assembly for biological agent separation and purification.
The use of biological activated magnetic particles or beads as carriers for biological agent separation and purification is well known. Several hand-held magnetic microplate assemblies are commercially available for separating biological activated magnetic beads from a supernatant and assaying the beads. Such separators may include a magnet base and a microplate having a plurality of wells (typically six, twelve, twenty-four, forty-eight or ninety-six wells) for retaining biological activated magnetic beads attracted by the base. In order to assay biological activated magnetic beads, the beads are delivered to the wells in a supernatant, and the beads are attracted to and retained in the wells by the magnet base. The supernatant is separated from the beads and discarded by inverting the microplate such that the upper surface of the microplate generally faces downward. A wash buffer may thereafter be applied to wash the beads in the wells, and the wash buffer may be discarded by inverting the microplate.
During the process of inverting the microplate to discard the supernatant and the wash buffer, the microplate and the magnet base must be held together in order to prevent the loss of any magnetic beads from the wells. In some known magnetic microplate assemblies, the magnet base and the microplate are held together with one or more rubber bands that are wrapped around the magnet base and the microplate. Because the rubber bands tend to trap supernatant and wash buffer and tend to shift their positions during the washing step, the rubber bands can cause cross-contamination of assays.
It is therefore desirable to provide a magnetic microplate assembly that includes improved means for securing the microplate during inversion of the assembly for discarding supernatant and wash buffer.